Greens leader urges SA not to go Liberal

Federal Greens Leader Richard di Natale has taken a swipe at the South Australian opposition, specifically urging voters not to elect the "destructive" Liberals at the March state election.

Mr Di Natale launched the Greens' election campaign in Adelaide on Saturday and in an emailed message to the party faithful called for the return of upper house MP Tammy Franks.

"We have two months until election day, which gives us two months to give everything we've got to get Tammy Franks re-elected to the upper house and keep the destructive, bigoted, backward Liberals out of power," he said.

"Tammy is the real deal. She is full of courage and compassion, two things that we need so much more of in our parliaments."

The Greens are not expected to challenge for a lower house seat in SA on March 17 and will need the party's vote from the previous election to hold up for Ms Franks to retain her spot.

A big challenge is likely to come from candidates on the upper house ticket for SA Best, the party headed by former senator Nick Xenophon.

Mr Di Natale said the SA election was also crucial for the rest of the country.

"As (Prime Minister) Malcolm Turnbull considers an early election and his ministers do their best to create fear and division in our community; we cannot let South Australia fall to the SA Liberals," he said.

With Mr Xenophon's party enjoying strong support in the opinion polls, the outcome of the SA election is almost impossible to call.

Recent changes to electoral boundaries will also play a role in deciding the outcome with the Labor government actually needing to increase its vote in some seats it currently holds to keep them in the Labor fold and retain office.

Mr Xenophon is standing for his local seat of Hartley and said previously he hopes his party can seize the balance of power.